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Corrosion of metals is producing huge costs by the depreciation of corroded structures with major impact on environment and human safety. It requires the proper selection of a specific protecting coating material. Innovative ways of counteracting corrosion by use of electrospun polymeric nanofibers will be reviewed. The use and benefits of single-component nanofibers for improving the mechanical properties of organic coatings are described. A further approach is the incorporation of corrosion inhibitors within the nanofiber structure in order to increase corrosion coatings performance. Attention is given to core-shell nanofibers using coaxial electrospinning setups for providing self-healing capabilities. The self-healing performance of various composite coatings reinforced with core-shell nanofibers is discussed. Literature results of improved corrosion resistance by nanofiber introduction into coatings are summarized. An outlook is provided for future potential ideas and possible applications of this emerging field. The commercial viability of those innovative processes is discussed and evaluated.

The use of smart nanocontainers as carriers of corrosion inhibitors offers good alternatives to the classical corrosion protection methods. This chapter aims to give a concise review on the most important recent achievements in the field of development and fabrication of protective coatings based on corrosion inhibitor loaded–smart nanocontainers, as well as explanation of the different corrosion inhibition mechanisms. The most significant types of smart nanocontainers have been demonstrated from polymer nanocapsules, nanofibers, nanotubes, and nanolayers to the porous nanoparticles. The commercial viability of those innovative materials and processes, as well as the advantages and limitations associated with their practical applications are discussed and evaluated in the chapter.

Electrospinning, an electro-hydrodynamic process is a versatile and promising platform technology for the production of electrospun nanofibrous materials consisting of diverse polymers and polymer composites. This platform process has provided bio- or oil based polymer nanofibrous materials for the fabrication of innovative biomedical devices and for the fabrication of new technical applications. By forming an interdisciplinary knowledge platform, the Action has strengthened the European R&TD on electrospun nanofibrous materials and nanofibrous composites and generated fast progress in the state of the art. The Action has covered scientific breakthroughs and innovations in the electrospinning process itself, nanofibrous materials and nanofibrous composite advancements and the post treatment processing of electrospun materials. Applications in the biomedical and technical fields as well as health, societal and environmental issues have been considered. The main outcome of the Action has been: New integrated methodologies for designing and producing electrospinning nanofibres Databases of application-relevant electrospun nanofibre properties An up to date knowledge base on electrospun nanofibres and its applications Tutorial material for training young researchers entering the field.

Ultrafine grained WC–0.6VC–10Co hardmetals are produced by monoaxial vacuum hot pressing (MVHP) between 1280 and 1320 °C around the eutectic temperature of the alloy. The microstructure and properties of the resulting hardmetals show that fully densified alloys can be obtained when MVHP is carried out at temperatures ≥1300 °C starting from commercially available ultrafine WC and cobalt powders. In the fully densified hardmetals, the grain size of WC is not increased. The average grain interception is between 169 and 179 nm and hardness values are over HV 30 2000. The Palmqvist toughness ( K c ) of the hardmetals increases with sintering temperature; the highest value obtained is 517 N/mm at 1320 °C. The distribution of the Co binder is almost completely homogeneous at micro level but still inhomogeneous at submicron level. In order to further improve the toughness of the ultrafine WC–VC–10Co hardmetals, the optimization of the composition, the use of pressure-assisted liquid phase sintering, and the optimization of the milling regime are discussed.

Combustion reaction 3TiO2+3C+4Al⇒3TiC+2Al2O3 has been studied by X-ray diffractometer (XRD), differential scanning calorimeter (DSC) and differential thermal analysis (DTA). The exothermal combustion reaction was observed at a temperature of about 1000°C. Poor wetability between liquid Al and TiO2 (or graphite) solid particles results in an undesired, inhomogeneous microstructure through direct combustion hot-pressing. In the present work, the reaction 3TiO2+3C+4Al⇒3TiC+2Al2O3 has been modified into two separate steps: (1) room-temperature treatment: 3 TiO 2 +3 C +4 Al ⇒ amorphous phase ( not identified yet )+ Ti , (2) reaction hot-pressing: amorphous phase + Ti ⇒3 TiC +2 Al 2 O 3 . A sudden shrinkage was also observed around 1000°C during reaction hot-pressing. Since no liquid phase appeared during reaction hot-pressing, a high-performance Al2O3+TiC ceramic composite with sub-micron grains and homogenous microstructure was manufactured.

Functional textiles are one of the most important fields in textile industry and textile materials science. They include breathable, heat and cold-resistant materials, ultra-strong fabrics (e.g. as reinforcement for composites), new flameretardant fabrics (e.g. intumescent materials), optimisation of textile fabrics for acoustic properties, etc. Functional textiles became more and more important materials for various applications and interest in them grew year by year; and more and more conferences are focused on functional textiles, as well as the events which are not only textile conferences but encompass various fields of Material Science. This paper presents a short overview about the European Materials Research Society 2014 Fall meeting conference Symposium M “Functional textiles - from research and development to innovations and industrial uptake” and the projects which participated as symposium co-organisers: the European Coordination Action 2BFUNTEX funded by the EC 7th Framework Programme NMP, the COST Action MP1105 on “Sustainable flame retardancy for textiles and related materials based on nanoparticles substituting conventional chemicals (FLARETEX)” and the COST Action MP1206 on “Electrospun Nano-fibres for bio inspired composite materials and innovative industrial applications”.

Embrittlement of tungsten heavy alloys is often caused by trace impurities. Heavy alloys containing O, Al and Si, respectively, were mechanically tested and exhibited interfacial embrittlement. SIMS analysis of metallographic sections was found to be a suitable tool for comparative analysis of heavy alloys with different fracture behaviour, the results obtained being not dependent on the fracture mode as is the case e.g. with AES. It was found that oxygen may cause embrittlement at the interfaces even at low overall content, since it is enriched at the phase boundaries tungsten-binder. Al is detrimental if it covers the interfaces rather evenly; grossly inhomogeneous distribution is less harmful. Generally, the distribution of trace elements is much more important than their total amount.

The divertor of a near-term fusion device has to withstand high heat fluxes, heat shocks, and erosion caused by the plasma. Furthermore, it has to be maintainable through remote techniques. Above a...

The interface composition and bonding of thin organo–tin polymers, plasma‐deposited on Al, are determined by AES, ESCA, and pull testing. A tin oxide species is formed between the bulk organo–tin polymer and the Al surface within an interfacial region of about 10 nm. This is evidenced by the change in the profile of the Sn‐MNN Auger signal and by the energy shift of the Sn 3d3/2 and 3d5/2 peaks in the ESCA spectrum. No tin oxide formation is observed at the interface of organo–tin films deposited under similar conditions on stainless steel. The composition at the interface is also shown to depend on the position of the sample in the glow discharge during film deposition.

The question whether some crystallization will take place in old glass during long-time storage (up to 1000 years) at low temperatures well below Tg is considered theoretically. Evaluations for the systems Na2O · SiO2 and Li2O · 2SiO2 are carried out using the model of homogeneous and heterogeneous nucleation theory. For these systems a barely observable crystallized volume fraction will be reached at 300 K only after storage for astronomical periods (106 − 1013 years), depending on the number of heterogeneities and the contact angle of heterogeneity. If the observed strong influence of H2O content in glass on crystallization is also taken into account, crystallization will not take place for at least 1000 years of storage at 300 K. This limiting value is close to archaeological periods and will therefore merit careful attention in further investigations.

Glow discharge films with various ratios of carbon to tin were deposited on various metals and on glass. The ratio of carbon to tin was determined quantitatively by X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES). The AES data correlated well with the XPS data. The X-ray beam and electron impact effects on organo-tin films influence the composition and are discussed in detail. The ratio of carbon to tin was not constant throughout the glow discharge reactor and this inhomogeneity is accounted for by the prevalence of “atomic” polymerization rather than “molecular” polymerization. We demonstrated that the substrate material had a definite influence on the composition of the films.

Semiconductive and conductive films of metallic appearance are formed by glow discharge of appropriate organometallic compounds. Tetramethyltin is used as a starting compound for the film-forming experiments. The resulting films contain carbon, tin and hydrogen with a carbon-to-tin atomic ratio of 2.5 or less. These films are semiconductors with conductivities between 2 × 10-1 and 1 × 10 -2 Ω -1 cm -1 . Transmission electron microscopy shows the films to be amorphous. Films of a certain composition are transformed to β-Sn on exposure to an electron beam. Thermal treatment increases the conductivity gradually to values of about 1 × 10 2 Ω -1 cm -1 .

Microprocessor-controlled analytical methods produce large amounts of data in a short time. This wealth of information is difficult to handle with conventional methods. Numerical classification is a valuable tool for reducing large arrays of data and revealing structure therein. Non-hierarchical methods have been used with good results for the classification of spectral analytical data of ancient glass samples. With the newly developed program “APART”, a classification was obtained according to technological aspects of glass production. The narrow clusters found were caused by local traditions and the use of similar raw materials. The colouring materials and decolourants contribute most to the trace element content, and are therefore dominant in the classification.

For analysis and understanding of complex analytical data the search for internal structure, if there is any, will be the most promising strategy. A non-hierarchical clustering technique has been employed for this purpose. The important question of how many clusters will represent the structure of the data matrix can be determined by an algorithm which gives a measure for the clustering significance of the distribution into a number of clusters. The distribution with a high clustering significance will then be taken as the distribution which resembles the internal data structure best. The algorithm and its performance is demonstrated. Two examples of industrial practice are shown. The technique proves useful for the control of raw materials quality by their trace elements and for the evaluation of a number of cemented carbide compositions by their physical and chemical properties. The obtained distribution into groups reflects the technological properties of the alloys very closely. An easy understanding of data structure and interrelations of elements can be obtained by this approach.

Mechanisms for carbide formation due to argon ion etching of silicon with resultant interference in auger electron spectroscopic analysis, are investigated. (AIP)

Seit den Untersuchungen von Cochardtl an Co-Basis-Legierungen ist bekannt, das geringe Zusatze von Hf die Kriech- und Kerbschlageigenschaften dieser Legierungen gunstig beeinflussen. Auch in Ni-Basis-Superlegierungen konnte durch Zugabe geringer Mengen von Hf (bis ca. 2%) eine Verbesserung mechanischer Eigenschaften bewirkt werden.